A striking symbol of the Bulgarian capital.

This enormous abstract sculpture is part jungle gym, part elaborate noise-making machine.

The first mosque in the world to receive electricity.

Some of the best-preserved specimens of the monumental medieval tombstones found throughout Bosnia and Herzegovina.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

Inat Kuća, or "House of Spite," is more than just an oddly named restaurant.

This ironic war memorial thumbs its nose at a campaign of inedible humanitarian aid food products.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

Oriental bazaar in the heart of Sarajevo.

A war-torn Olympic relic is being overtaken by graffiti and nature.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

Bridge that died in war and was resurected.

Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

The apartment building where JFK's assassin lived after defecting to the Soviet Union.

Glowing orb in Minsk houses 8,600,000 items.

Thanks to its heroic service during WWII this Soviet castle has been turned into a monument towered over by a brutalist titan.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

Austria's ultra-modern art museum looks like Cthulhu's giant alien heart.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

The world's oldest known salt mine.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Baroque celebration of the end of the Great Plague of Vienna.